Formation of metal strip under controlled pressure



FORMATION OF METAL STRIP UNDER CONTROLLED PRESSURE Filed Jan. 30, 1953 2 Sheets-Sheet. l

BY 924a,... qd- 21AM INVENTOR.

ATTORNEYS.

Dec. 20, 1960 J. B. BRENNAN 2,965,513

FORMATTON OF METAL STRIP UNDER CONTROLLED PRESSURE Filed Jan. 30, 1955 2 Sheets-Sheet 2 F l V// //7//////} A 92 INVENTOR. 29 7 JOSEPH a. BRENNAN 2,955,513 Patented Dec. 20, 1960 FORMATION OF METAL STRIP UNDER CON- TROLLED PRESSURE Joseph B. Brennan, 13018 Lake Shore Blvd., Cleveland 8, Ohio; Helen E. Brennan, executrix of said Joseph B. Brennan, deceased Filed Jan. 30, 1953, Ser. No. 334,130

4 Claims. (Cl. 117-93) The present invention relates to the continuous pro duction of metal strip as such, of a composite strip of which one component is produced according to my process and another component is a metal strip or preferably a. porous or fibrous strip. Composite strips which include such a porous or fibrous component and the metal strip applied thereto by my method are adapted for use as inelectric condensers, for example.

The present invention relates to certain improvements over the methods and apparatuses shown in my co-pending applications Serial No. 43,881, filed August 12, 1948, now Patent 2,639,490, and Serial No. 324,020, filed December 4, 1952, now Patent 2,870,689. This application is also a continuation-in-part of my application Serial No. 744,727, filed April 29, 1947, and now abandoned.

One object of the present invention is to provide a method by which an elongated metal strip of desired uniform characteristics is continuously produced by spray discharging at constant temperature and under the influence of constant pressure molten metal against a uniformly moving heated base member of which base member the spray deposited layer either becomes a part, as aforesaid, or from which base member the spray deposited layer may be continuously removed as a separate metallic strip.

Another object of this invention is to provide a method of continuously producing metallic strip of the character referred to by spray discharging of molten metal without the usual gaseous blast as is required in conventional metal spraying processes.

Still another object of this invention is to provide a spray method of continuously producing metallic strip wherein vaporization of the sprayed metal particles is achieved without requiring a separate gaseous blast for the breaking up of the particles as discharged through a spray nozzle.

Another object of this invention is to produce finer grained and/or finer and smaller particles by spray depositing metals than has heretofore been obtainable in the spray projection of metal particles.

With reference to the formation of metal impregnated porous sheets or fabrics, these have been previously made by spraying metal against a porous band, such as 40 mesh cotton gauze, thin paper, or asbestos, and usually the molten metal is sprayed from a stationary spray gun onto such band as the latter is moved past the gun. In order that the sprayed particles will adhere to the porous band, the metal particles should be plastic when deposited and should also be uniformly distributed so as to substantially uniformly coat the band. However, it has been difiicult to coat wide hands by the methods known heretofore; and, in fact, prior processes have been used to coat only narrow bands, such as 3 or 4 inches wide. Furthermore, the temperature of the deposited particles must be held within very close limitations to have the desired plasticity when deposited so as to interlock on, and adhere to, the fibers of the porous band. .Hence, previous types of porous sheets of this class have not been uniform and have been expensive to manuf acture.

Hence, it is another object of this invention to avoid and overcome the foregoing and other difficulties with prior types of processes for producing porous sheets for use as electrodes and to provide an improved method of obtaining uniform sheets characterized by its ability to be used with any type of metal particle deposit apparatus.

Another object of the invention is to utilize suction in.

depositing metal particles on a base sheet.

Another object of the invention is to provide a method of uniformly covering a wide base with metal particles which are integrally bonded to each other and to the base.

Another object of the invention is to control the temperature and velocity of the metal particles as they are in transit towards the moving base sheet.

Yet another object of the invention is to roll out, spread, or press the metal particles, while in plastic condition, against and into a porous base sheet.

A further object is to provide a control for the deposit of metal particles on a base sheet.

A further object is to accelerate the deposit of metal particles on a base band.

Still other objects of the invention are to secure uniform plasticity in and velocity of metal particles as they are being deposited on a base; to form an oxide coating on the metal particles as they are deposited; and to collect the unused metal particles in the stream in an economical manner.

Other objects and advantages of the present invention will become apparent as the following description proceeds.

To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principle of the invention may be employed.

In said annexed drawings:

Fig. 1 is a diagrammatic view of apparatus embodying and for practicing the principles of the invention;

Figs. 2 and 3 are similar views of modified apparatus for use in practicing the invention;

Fig. 4 is a side elevation view, partly in section, showing schematically one form of apparatus for performing the present process wherein the spray deposited metallic strip constitutes one component of a composite strip;

Fig. 5 is a cross-section view on a somewhat enlarged scale along the line 5-5, Fig. 4;

Fig. 6 is a fragmentary view showing a modified apsecuring a fine division of sprayed metal without requiring a gaseous blast;

Fig. 9 is a view similar to Fig. 8 except illustrating a different form of spray nozzle also for achieving desired fine sub-dividing of molten metal without requiring a gaseous blast;

Fig. 10 is a bottom plan view of the Fig. :9 spray noz zle' as viewed along the line 10-40, Fig. 9; and

Fig. 11 is a cross-section view illustrating one manner of producing uniform thickness metal strips by my process in instances where the distribution of the sprayedpar ticles is the most concentrated at the center of the spraycone and progressively less concentrated around the periphery-thereot.

Now referring in detail to the drawings, a base sheet 10 is provided which passes from a storage roll 11 around an=idlerroll 1-2 to a wind-up roll-13, which maybe-drivenin a conventional manner. from cotton cards, gauze, porous paper, fiberglass, etc., or" the sheet could be made from cotton cards with cellulose acetate fiber therein with the latter sheet material usually being rolled while heated prior to its use in accordance with the teachings of this invention. In all events, thesheet-lOis impregnated with metallic particlesas it passes from the roll 11 to wind-up roll 13 tO'fOlmi a porous metallic sheet. To this end there areshown suitable spray nozzles 14 and 15- for blowing metallic particles P against. the sheet 10 asit is drawn along its pathbetween the rolls. The nozzles 14 and 15 are provided with a metal supply" and their functioning is no part of the present invention. The nozzles deliver an air blast which has liquid, or plastic metallic particles therein that are to be deposited on the base sheet. This particle stream cannot be released immediately adjacent the-sheet 10 or it would not deposit in the form of a porous layer, as is desired. Hence, the nozzles'14 and 1-5 are spaced from the sheet 10 with the spacing shown in. the drawings being exemplary only. Due to such travel, the plastic metal particles in the blast cool rapidly,- partly due to the: expansion of the carrier gas and partly to striking the atmosphere. As hereinafter explained, thenozzles can operate-without a separatea-irblast.

Asraisalient feature-of thesinvention, a suction isprovidedrto -aid l indepositing themetal particleson and in The amount ofsuction canbe varied the effect; of the suction may be enhanced, if desired, by

providing extensions. on the suctiontubes. The extensions (not shown) could be placed between the doubledf portions of the base sheet in alignment with the nozzlesand even have sections telescoped' over the ends of the nozzles, ifdesired.

As .a further featureof the invention, heating means, such as induction coils 18, are placed between the doubled sections of the sheet 10 in alignment with thenozzles andsuction tubes. The coils 18 have a high frequency electrical current supplied to them by any conventional source so as to set up a heating field therebetween sufficient to heat small conductive particles substantially instantaneously as they pass therethrough. Ordinarily, the metal particles will be at an elevated temperature when they reach the coils 18 which then would at least maintain their temperature at a desired level.

By use of suction as an aid in depositing metal particles on the base sheet 10, combustion ofsuch sheet, if combustible, is prevented due to the excellent temperaturecontrol effected. The coils 18-are usually present to.

aid'in controlling the temperature of the deposited particles which should besufiiciently plasticand be moving at such a high velocity as to spread somewhat over the sheet-on impact. Deposit of the particles by suction also permits them to be originally propelled by alow pressure gas,- which then would be used in large volumes.

However, in some instances, no propellant gas isrequired' as when employingnoz zles of the type shown in Figs. 8 and 9, for example.

Toaidin-securing the-metal particles '1? to and; in the,

sheet 10, it maypass between pairs of rolls19, 2,01 and 21 which may compress thesheet 10 slight y t aidin.

The sheet may be madeintegrating the metal particles with the sheet. The pairs of rolls at lease flatten the metal particles extending fartherest from the sheet and serve to bind the metal particles and sheet together firmly. The pairs of rolls 19, 20 and 21 have a high frequency electrical current supplied thereto by pairs of leads 23, 22 and 24 connected thereto and to a source of such energy. These rolls 19-, 21; andZlLmay-be formedfromany desired material which is not electrorconductive and may comprise a ceramic or a dielectric material with the high frequency coil or platemeans or otherdevice being posie tioned thereinto setup a high frequency field there between. Hence, the combined pressure set up by the rolls and he nlasticizi at'e feet et up: y: heat the deposited particles producesapermanent bond between the metal particles'and the base sheet and/or fibers thereof. The bonding is especially important for the first metal deposited on and in the sheetso that the rolls 1? are of especial value, while the rolls-20 and-21; may be omitted, when desired.-

The material deposited by the invention usually is aluminum, but othermaterials or mixtures of materialssuch as magnesium, tantalum, aluminum oxide, etc., couldbeused. It may even be-desirable to includesome fibers or filler-particlessuch as boric' acid or particles or fibers of a synthetic thermoplastic like cellulose acetate in some instances.

The metalparticlesdeposited could; be in particle form prior to. such depositaction and in that case could be carried bya-vibratingscreen and usually be star-ted toward thebasesheet by-gravity or asuction action; Also, the-particles-couldbe mixed with a carriergas: a cyclonic-- mixer and passed" therefrom to the base sheetz In such modifications, the particles: couldbe heated-in anydesired manner asby passing through additionalcoils, like-coils 18, prior to deposit on the base sheet.-

If the base-sheet'1'0 isto beused in making porous electrodes, production of the desired porosity is expedited; by;

placing aluminum oxide, mica, or other non-conductive tubing within the bores of the coils 18 and having the metal particles flow through such coils. The tubing also will prevent theparticles from depositing on the coils.

Fig. 2 of the drawings show how two base sheets 30 and'31'can have metal particles P sprayed between them to aid' in bonding the sheets together and in metalimpregnating them. The sheets passbetween a pair of rolls 32 immediately after the particles strike the sheets. Suction tubes 33 and 34 are provided to aid in the particle deposit, as hereinbefore explained. As in the apparatus: of Fig. l, the rolls 32 may have high fre quency current supplied thereto, if desired, and atem' perature control coil may also be providedbetween thesheets 30 and 31 as shown. The converging base sheets 30 and 31 form a bight therebetween and metal particles deposit in the bight as well as on the adjacent portions of the base sheet.

Apparatus. for coating opposite sides of a base sheet 48 is disclosed in Fig. 3. Nozzles-41 and 42 are providedto direct streams of metal particles against opposite surfaces of the sheet 40, while suction tubes 43 and 44, respectively, are aligned with the nozzles. Again, heating rolls and coils maybe used if desired.

The suction depositing action helps to distribute, uniformly, the metal particles being deposited and permits;

any of several types of metal deposit rneans to be used so-that wide base sheets can be uniformly covered with metal both laterallyand longitudinally ofthe base sheet. 7 Such uniformity is extremely'desirable inmakingcondensers and a uniform capacity sheet which. can be efii ciently and rapidly produced, is provided by the invention.

By heating the metal particles, such as aluminum, in

to finis h r ul t h j normallyhas an such as an anode in an electrolyte.- The partially oxide coated metal also may be processed and electroformed at I lower current cost than unoxidized metal.

The oxide film on the surface of the metal particles is punctured on deposition and impact permitting the molten or plastic metal inside each particle to make good, low resistance electrical and intimate physical contact with the porous base sheet, resulting in a flexible, porous layer of particles if kept thin enough, preferably about .010 inch in thickness, but not over .125 inch,

Also according to my invention, the same sheet may be Multiple sheets may also be metallized simulmain in the atmosphere adjacent the depositing apparatus.

Referring now to Figs. 4 and 5, the apparatus there shown comprises a molten metal supply crucible 51 into which molten metal or solid metal particles may be continuously or intermittently supplied as through the charging passage 52. The metal in said crucible 51 is heated to molten condition or is maintained in molten condition by means of the high frequency induction coil 53 -or equivalent heatingmeans associated with said crucible.

Leading from said crucible is a' discharge conduit 54 to 4 which .the intake port of av pump 55 or the lik e is coltnected, the molten metal displaced by said pumpbeing discharged under desired pressure through the. spray nozzle 56. The metal flowing through the spray noule.-. at desired pressure is maintained at a desired temperatureand fluidity as by means of the high frequency induction heating coil 57 therearound. Obviously, other heating means may be employed, such as electric resistance heaters, hot fluid circulated through the passages in the nozzle, or equivalent heatingmeans. The crucible 51 is also provided with another passage 58 through which gas under pressure or inert gas may be admitted; and, when pressure gas is employed, the pump 55 m y,.in some instances, be omitted so long as the pressure gas is uniform and the static head of metal in said crucibleis maintained constant so as to secure uniform spraying.

The molten metal from the spray nozzle 56 is sprayed intoan enclosure 59 which is preferably maintained under partial vacuum as by means of the passage 60 connected to a suitable vacuum source.

Within said enclosure is a supply roll 61 ofstrip mate: rial 6 2 which, for example in the production of electrodes for electric condensers, comprises paper or other porous or fibrous filament belts, cords, yarn, or gauze of refractory material such as asbestos or quartz. In order to prevent spraying of the edge portions of said strip 62, a folding device 64 is provided which folds under the opposite edge portions of said strip 62 as best shown in Fig. 5. Inasmuch as the strip 62 is at a temperature at or above the melting point of the sprayed metal, the sprayedparticles will immediately coalesce and when solidified, there is produced a metallic strip 65 of the.

desiredporosity; and, if desired, the composite sprayed layer 65 and strip 62 may be passed between squeeze v relation therearound.

dition at the time that they impinge upon said base strip.-.-

and for this purpose, a high frequency coil 69 has been found to be the most eflicient especially when arranged as shown to encircle the spray field in uniformly spaced gas furnace may be employed.

Where composite strip is desired, the base 62 may be In some instances, an electric or heated to a temperature above the melting point of the ;bonded metal coating is desired on said base.

quent coating of a more porous nature may be applied 7 after a first bonding coalescing molten metal bonding spray.

particulate In instances where it is desired to produce metallic j strip as such, it is preferred to employ an endless highly polished metal band 70 as in Fig. 6, which passes overi guide rolls 71 and 72 and is driven by one of them so-g,

that at least one stretch of said band moves underthe spray at a uniformlineal speed. Again the process is; y

conducted under a partial vacuum in an enclosure 61 5 and a suitable stripper 73 is provided to separate the spray deposited layer 74 from said band 70, whereupon the,

spray deposited layer may pass through pinch rolls 75 and be continuously wound around a take-up noll 76;

by means of an apparatus such as illustrated in Fig. 7

wherein a rotary drum 80 is provided against whichthe It is also contemplated to perform my unique process spray is directed and from which drum. the spray deposited layer 81 may be continuously removed with the ;,,spray deposited layer passing or not between pinch-rolls;

82 and being wound on a take-up, roll 84. The drum surface, therefore, .in effect, constitutes an endless band corresponding to band as-shown in Fig. 6 and, ifit is desired to make composite strip as is done in the Fig.

4 apparatus, a base'strip such as 62 may be Wrapped around said drum and the spray directed against said base strip. In such instance, the edges of the base strip f prevent spraying onto the may again be folded under to opposite edge portions thereof.

It will be obvious to those skilled in the art that various modifications may be made in the apparatuses herein disclosed.

One important feature of my process as hereindisclosed, is that it is not required to employ an atomizing gas or gaseous blast for the sub-dividing of the molten metal. In the spray nozzle disclosed in Fig. 8, the molten metalis caused to flow through several small passages.

85 which converge so that the streams issuing therefrom will collide with one another and thereby effect a breaking up of the molten metal into very small particles. For example, when spraying molten aluminum at a temperature of 1800 F. and at a pressure of 30m p.s.i.

through .005" passages, the average particle size will be under 10 microns.

The spray nozzle illustrated in Figs. 9 and 10 includes an orifice plate 90 which has an orifice 91 therethrough terminating in an oblong groove 92 on its outlet face which is elfective to break up the stream into line particles x and to spread the same in the form of a relatively narrowfan. Here again, no gaseous blast is required in orderto break up the molten metal into extremely fine particles suitable for the practice of the present invention;

In instances where the sprayed particles are not uniformly distributed in the spray field, uniform thickness 1 metal strip maybe produced by having, forexample,

three spray nozzles staggered relative totbe pathof the rollers 66 when hot and then the composite strip 65-62 was is Quiet 9 ea ises t e ies, in. who" as:

base strip so that the aggregate of the. three non-uniform deposits over the width W will be of uniform thickness. Obviously, instead of providing several spray nozzles as aforesaid, it is possible to obtain the sameresults with one nozzle by successively passing the base strip 96 under different portions of the spray cone. For further,

reference, attention is directed to the Robert M.,Brennan Patent 2,598,344 which was granted on May 27; 1952, and which discloses an apparatus and method by l 7 uni-form -thickne'ss"spray depositedlayers of metal are produced? The *present invention: also concerns the vaporization of 'metal fr tlfe' production of elongated" metal strip, againwithout requiring a a gaseous blast. effect extremely fine division'of the molten metal, the same issupefiheated'and discharged into a space maintained l at a pressure (usually"a"partial vacuum) at which the"super=heated metal will vaporizeand, in effect, the vaporized met'al will condense upon thebase strip. For thispurp'ose; the space into'which the super-heated molten metal is" discharged is" preferablymaintained under a partial vacuum so that the extent of super-heating need" no'tf b e' 'as great' as when thespace isat normal atmospheric' pressure or at some super-atmospheric pressure;

anddirectionalfdeposition is achieved as'well as increased production:

' My processasherein disclosed, is applicable with" virtually all 'metals and alloys," among which are included for example; titanium, nickel, copper, lead, aluminum.

A" distinctive featureof this invention resides in that particulate moltcn-material is" deposited onto, or impregnated' in -a fibrous "base which base is maintained at an elevated temperature'equal to, or in excess ofthe melting'pointof thedeposited particulate molten material during the time of deposition or thereafter with the result that" the" particles" of molten material coalesce with the fibers ofthe basematerial and join, and bond the'fibers" together to *produce a very'strong'material when thereafterthe-deposited'molten metal particles are solidified.

This" material isstr'ength'retaining up 'to' the'melting" point; orsofte'ning point," of "the" molten particulate materialdepo sited aiidcoalescedwith the fibrousbase ma= terial.

The'methods of associating'the fibrous'material and the molten particulate'material" are, forexample, described injmy copendingapplication U.S. Serial No. 324,020, filedDecember'4, 1952, now Patent 2,870,689, and also in my co-pending application U.S. Serial No. 43,881, filed August'll, 1948', now Patent 2,639,490.

According tothis invention, any kind of fibrous material may be used so long astit will withstand the temperatures'involv'edwhich are equal to or in excess of the'meltingpoint of .themolten material applied thereto forbondin'g'andmaking"a strong fabric. The particulate molt'err'material'maybe, for example, applied in continuous layer formi'to the fibers while molten or solid and"ffisefandcoalescedthermally immediately or sub sequently andtlienchilled'to solidify and "effect the bond ing -action"; Such a layer may be applied by spraying;

spreading," or by othermeans', but in any case, the metal.

a"unifor"m-"rate"during -theapplication of the metal'pan' ticles' tliereto 'and such baseis constantly heated to coal-escethe metal iparticles atf orn'ear the point of 'application"and th'ereafter' cooled to solidify the'm'etal particles; f

Meltable or sinterablewnetal particles may, of course, be applied in' continuous condiictive layer form also as can" readily b'einiderstootl either in a single' or multiple opera tioni,

In order to i 8 By havingthe base and the applied metal particles at;

or abovethe melting point of the metal particles and then chilling the'compositematerial; a material atleast several times'as strong in tensile compared to thefibrous base aloneis produced.

Material I so-produced may be conductive throughout if 'theap'plied particles are welded together and abutting,

orit maybe conductive in some areas and non-condu'ctive in'others,-depending upon the densityand pattern and distribution. In any case, a fabric is made according to this' invention which is many times as strong as'the untreatedfibrous base material'and'capable of withstandingtemperatures whileretaining its great strength up to the heat softening: pointof the bonding particulate material.

Initia'For" subsequent layers of particulate bonding materialsmay'b'e applied'to one side only of the'refractory' fibrousbaselayer so that a continuous composite-coherentconductive layer which is non-porous and' irrn pervious may be produced in continuous strip form.

Non-porosity in-theapplied metallic layer is produced by heating the applied metallic layer beyond its melting point while associated with the fibrous base layer of refractoryfibers. used which will withstand the temperatures involved without objectionable change;

Othermodes of applying the principle of the-inventionmay be 'employed," change being made as regards-thedetails described, provided the features stated inany of the following claims, or the equivalent'of such, be employed.

I" therefore particularly point out and distinctly claim as 'my 'inventi'on:

l. The method of continuously-producing metal-*strip comprising spraying molten metal a from a spray orifice under the influence of uniform pressure and'inthe ab sence of a gaseous blast toward a-base' member" to dis-" charge-such metal as a particulate spray, heating the particulate* spray subsequently to its discharge from the' spray orificeandprior to its reaching the base member to maintaint'he particles ther'eof in a molten plastic con dition, and'thendepositing'the metal whilestill in such plastic condition in'strip form'on such base member:

2. The method of continuously producing" metal strip on" a base member comprisinghydraulically spraying molten metal from aspray" orifice "under :the influence of uniformpressureand' in the absence ofia gaseous blast through a discharge area toward such base member, evacuating the discharge area to discharge the. molten metalifrom' such orifice under a sub-atmopheric pressure, heating the molten metal spray subsequent to its leaving the spray orifice and prior to itsdeposition on such baseby high frequency electrical energytoj avoid varyingfsuch sub-atmospheric pressure, andl'then-depositing, the sprayed metalwhile still'in such molten plastic condition on such basemernb'er in strip form;

31 The method" of continuously producing metalstrip on a. base member comprisingv hydraulically spraying,

molten metal from a-spray. 'orifiee' under the influence of uniform pressure and inthe absence of a gaseousblast- 'atto discharge such metal toward the basemember as a spray of' particulate molten metal, heating the molten.

metal spray,v subsequentto its leaving the. spray orifice andipriorto its deposition on such base by highifrequency electrical energy, movingthe base member angu larly into"'thesp r'ayand at. a uniform speed to deposituni formly thereon the molten metal particles while still in such molten plastic condition,tand then coalescingfthe depositedparticles to form a metal stripof uniform size.

4*. Themethodof" continuously producing metalstrip on a base" member comprising hydraulically'spraying moltenmetal' from a'spray orifice under the influence of uniformp'ressure and in'the absence of a gaseous 'blas t' througha discharge" area toward such' base member't'o dischargef suclr metal as a'spray ofp'articulate molten 75-metal,- evacuating the discharge area to discharge the In this case; refractory fibers must he molten metal from such orifice under a sub-atmospheric pressure, heating the molten metal spray subsequent to its leaving the spray orifice and prior to its deposition on such base by high frequency electrical energy to avoid varying such sub-atmospheric pressure, moving the base member angularly into the spray and at a uniform speed to deposit uniformly thereon the molten metal particles while still in such molten plastic condition, and then coalescing the deposited particles to form a metal strip of uniform size.

References Cited in the file of this patent UNITED STATES PATENTS 1,128,059 Schoop Feb. 9, 1915 1,671,620 Von Marchthal May 29, 1928 1,784,611 Polanyi et a1. Dec. 9, 1930 10 Fiedler Apr. 23, 1935 Hodson Jan. 16, 1940 Brennan Aug. 12, 1941 Mourer Aug. 19, 1941 Blackburn Sept. 29, 1942 Merle Nov. 10, 1942 Chapman Jan. 23, 1945 Batcheller Ian. 28, 1947 Robertson Dec. 6, 1949 Shephard Mar. 11, 1952 Brennan May 26, 1953 Brennan Feb. 8, 1955 FOREIGN PATENTS Germany May 13, 1923 Great Britain Apr. 21, 1938 

1. THE METHOD OF CONTINUOUSLY PRODUCING METAL STRIP COMPRISING SPRAYING MOLTEN METAL FROM A SPRAY ORFICE UNDER THE INFLUENCE OF UNIFORM PRESSURE AND THE ABSENCE OF A GASEOUS BLAST TOWARD A BASE MEMBER TO DISCHARGE SUCH METAL AS A PARTICULATE SPRAY, HEATING THE PARTICULATE SPRAY SUBSEQUENTLY TO ITS DISCHARGE FROM THE SPRAY ORFICE AND PRIOR TO ITS REACHING THE BASE MEMBER TO MAINTAIN THE PARTICLES THEREOF IN A MOLTEN PLASTIC CONDITION, AND THEN DEPOSITING THE METAL WHILE STILL IN SUCH PLASTIC CONDITION IN STRIP FORM ON SUCH BASE MEMBER. 